This concrete forming system relates to forms and methods for forming concrete panels in general and more specifically to a foam panel made integral with the concrete placed adjacent upon it. A unique aspect of the concrete forming system is a shaped channel in the foam panel that grasps a concrete tee or web located therein. This follows, secondly, the preformed groove that the forming boards are inserted into to create the shape of the formed concrete panel. The present invention employs expanded polystyrene as a layer in the concrete panel construction that produces a cost effective insulation system for a building.
For years, concrete has seen use in construction activities of many kinds. Concrete arises from a mixture of cement, water, fine aggregate, coarse aggregate, and additives. The mixture proportions can vary resulting in a wide variety of concretes. Overall, concrete begins in a plastic state and conforms to its container, commonly called a form. Once cured, concrete has a strong resistance against compressive loads and with steel reinforcement, concrete can resist tensile loads.
The American Concrete Institute regulates concrete as a durable, age old, and fire resistant building material. The Institute described and explained flat casting of concrete panels and then tilting the panels upwards to make a wall. The Institute printed publication 551R-92 “Concrete Tilt Up Structure” that explained the current state of the art in tilt up panels. Tilt up is a construction technique of casting concrete panel elements in a horizontal position at the job site and then tilting and lifting the panels to their final position in a structure.
Further, the federal government through various agencies has emphasized energy savings in construction, which can be achieved through usage of the construction method of this invention. In 2004, the Berkeley National Laboratory issued a report about electrical demand response. This report stemmed from the power crises that afflicted California in the early part of this decade. The report indicated that utilities, businesses, and consumers could cooperate to adjust demand for electricity in response to fluctuations in the spot price for electricity. The utilities would send a signal through the power grid that automatically disconnects equipment and users of electricity until the price lowers. Businesses and consumers would be compensated for the interruption in electricity by lower rates. Previously in 1992, the National Energy Policy Act required improved energy efficiency in commercial buildings and by other electricity users. Addressing the electrical demand and energy efficiency issues, the present invention provides insulation integral with a building wall. The insulation value of a panel constructed as the present invention inherently lowers heating and cooling costs. The present invention improves the energy efficiency of buildings of many descriptions and lowers the demand for electricity, commonly used for heating and predominantly used for cooling. The present invention is suitable for all types of buildings.
Another significant advantage of utilizing the laminar structure for forming a concrete-foam tilt up panel, is that the foam insulation further functions as a control for acoustics, which makes the wall panels fabricated in the manner of this invention very useful in the construction, for example, of buildings that require resistance to the transmission of sound, such as movie theaters, business offices, and related structures. The foam insulation resists the transmission of sound through a wall whether the foam is used separately or integrated into a wall panel. When placed into a wall panel, the foam insulation increases the resistance to sound transmission as it allows a contractor to incorporate an air gap between the interior wall finish and the foam insulation.
The present art overcomes the limitations of the prior art. That is, in the art of the present invention, a polymer foam panel is placed at the bottom of a form and concrete attaches upon the panel. The present invention displaces upwards of 30% of the mass of an existing panel or tilt up panel, and thus reduces the weight of a panel. The lower weight of a panel lessens the shipping costs and erecting costs associated with a heavier traditional tilt up panel. The present invention results in a stronger concrete panel with a higher strength to weight ratio when compared to a traditional tilt up panel. The present invention offers greater strength in the different states of concrete as it is placed, poured, trapped, or wrapped around the reinforcing steel into the panel of the present invention. The cost efficiency is a very desirable attribute of this invention. The present invention brings together insulation, structural reinforcement or metal studs, and concrete to produce an energy efficient insulated tilt up panel system. The polymer foam panel retains its shape as it provides a form for concrete that cures into a structural shape that bears the loads applied to a wall. The polymer foam panel incorporated into a concrete panel provides insulation with a higher R value, and displaces concrete thus saving weight while maintaining strength.
The polymer foam panel shape includes grooves for metal studs that serve as an attachment mechanism for finishes and provides a void that functions as an electrical or plumbing chase. Additionally, this invention uses the polystyrene foam to support a truly unique method of supporting forming boards that create the final shape of the concrete panel. The only method of forming wall panels in today's tilt-up or pre-cast industries is to set up metal, wood or plastic forms that create the final shape of the wall panel. This invention incorporates a special groove near the edge of the foam panel that enables a form to be quickly inserted prior to casting the concrete and then quickly removed following adequate hydration of the concrete. The invention eliminates the need for costly steel bracing, expensive laminated forms and the unavoidable damage to concrete floors that serve as an attachment surface for forms and bracing. In addition to these benefits, the labor cost to set up and tear down forms is substantially reduced.